In the printing industry, it is sometimes necessary to process media multiple times in order to create a final product. For example, media such as paper may be pre-printed in an offset press, then run through a digital press/printer in order to add unique (variable) information. In other instances, a digital printer may not have enough capability (e.g., an ink jet printer may not be able to print Magnetic Ink Character Recognition (MICR) data, or a monochrome printer may not be able to print color/highlight color).
In these cases, it may be necessary to process the media through multiple, independent digital printing devices in order to achieve the final product. To highlight their independence, the printing devices may be located in different buildings or countries and having no external network connection. Thus, the printed output may be processed hours or days apart.
When the independent printing systems are generating variable data (e.g., print data changes frequently and is very specific and personal to each piece of media), it is critical that each of the independent systems apply the correct data to the media. For example, the media may be processed in the first printer to apply a name and address in color, then processed in a different printer to add MICR data to be used by a banking system. Therefore, it is extremely important that the variable data printed by the two independent printing systems is matched correctly.
In many instances, there is no way of verifying the output of the second printer to determine if the second printer performed correctly. For example, the second printer may have printed a bank account number in MICR data, but there is no way to verify that the printed account number matches the account holder's name that was printed by the first printer.
Accordingly, a mechanism to verify the accuracy of data printed on the second printer is desired.